Bore-sighting device.



C. C. SHEPPARDE BORE SIGHTING DEVICE.

APPLICATION FILED NOV. 29, ms.

1,295,075. Patented Feb. 18, 1919 a Q g2 g'wue'nfoz L CGJ/Zeppard;

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CREEDY C. SHEPPARD, 0F BRIDGEPORT, CONNECTICUT, ASSIGNOR TO UNITED STATES ORDINANCE COMPANY, OF WASHINGTON, DISTRICT OF COLUMBIA, A CORPORATION OF VIRGINIA.

BORE-SIGHTING DEVICE.

Specification of Letters Patent.

Patented Feb. 18, 1919.

Application filed November 29, 1916. Serial No. 134,101.

To all whom it may concern Be it known that I, CREEDY C. SHEPPARD, a citizen of the United States, residing at Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Bore- Sighting Devices: and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

It is well known that the line of flight of a bullet is determined by the last portion of the bore of the firearm and in thecase of a rifle by the last few inches, this portion of the bore I will term the critical portion and the axis of this portion I will term the critical axis. Consequently, if the line of sight is parallel to the direction of the critical portion and to the critical axis of the bore the firearm should shoot correctly. It has been customary to adjust the sights of a firearm by targeting, that is by firing trial shots. observing the impact, and correcting the sights. This process or method is repeated until the sights are 'alined satisfactorily, but is slow and expensive and in addition requires the services of skilled targeters.

It is therefore the purpose of my present invention to provide an apparatus whereby the proper adjustment of the sights, so that the line of sight will bear the desired and correct relation to the critical axis of the bore, can be accomplished with ease and facility by unskilled labor and the expense or targeting eliminated.

I shall disclose my invention in the best form known to me at present; but it will be understood that it is susceptible to improvements in forms. proportions, and details of construction and to desirable additions, by the exercise of ordinary mechanical skill and without departing from the spirit of the in vention.

In the drawings chosen to illustrate my invention, the scope whereof is set forth in the claims. I

Figure 1 is a side elevation of a rifle supported on a fixture and showing my invention applied and with the sights adjusted through the medium of the invention;

Fig. 2, a plan view of what isshown in Fig. 1;

Fig. 3, a view looking at the muzzle end of the rifle in Fig. 1;

Fig. 4, an enlarged side elevation of my invention detached from the rifle and partly in section, and

Fig. 5, a front view of the invention.

In the drawings A indicates a fixture which supports a rifle B. This rifle embodies a barrel 10, a rear sight l1 and a front sight 12 all as is well known. My sighting device comprises an accurately made bar or rod 13 which is adapted to fit snugly in the critical portion of the bore of the barrel l0 and whose longitudinal axis coincides with the critical axis of the bore of the barrelwhen the rod 13 is inserted'in the barrel as shown in Fig. 1. When the rod 13- is inserted in the barrel 10 the coinciding axes of the rod and bore constitutes the line of departure of the bullet. This rod 13 is provided at its outer end with a pivot 14 on which is mounted a pendulum 15. A sighting bar 16 is carried on the upper end of the pendulum 15 and the ends of this bar 16 are provided with sighting apertures 17 so positioned as to determine a line of sight m-m which is parallel to the axis 'g ;1 of the rod 13 and of course parallel to the critical axis of the bore of the barrel 10 when said rod is inserted in the critical portion of the bore as previously referred to. It will of course be obvious that the pendulum 15 will hold the apertures 17 in a vertical plane and that the line of sight m-m will be parallel to and vertically above the critical axis of the bore. If desired the bar 16 and apertures 17' may be replaced by a telescope whose axis is parallel to the. axis 3,/ i

In the use of my device the firearm to be sighted is first placed in a fixture or stand A so that the sights 11 and 12 are disposed vertically above the axis of the bore. The rod 13 is then inserted in the critical portion of the bore of the barrel 10 as shown in Fig. 1. The pendulum 15 then positions the apertures 17 so that the line of sight w w is disposed vertically above the axis of the bore of the barrel. The operator then sights through the apertures 17 and moves the sights 11 and 12 until they coincide with the line of sight determined by the apertures of the sighting bar, when said sights will be in correct position and can be made fast. Means for compensating for drift, deviations of the bullet due to constant influences such unsymmetrical action of the arm, bayonet Whip, etc, may be added if desired.

.l/Ieans for adjusting the sight elevation so ah'at it will be correct for any given range nay be provided by inclining the axis of ;he sighting bar to the axis of the rod 13 it an angle corresponding to the elevation required.

A single aperture 17 may be provided in connection with the sighting bar 16 with which the front and rear sights of the rifle can be alined. This would of course be an approximate alinement but is in many cases sufficient for lateral sight correction.

I desire to state that my invention is in no way limited to disposing the line of sight of the sighting device parallel to and in the same vertical plane as the critical axis of the gun bore. As previously stated this line of sight of 'the sighting device might be disposed at an angle to the critical axis of the gun bore, and furthermore in cases where the sighting elements of a gun are disposed on one side the device would be correspondingly positioned to effect the adjustments of the sights. In the latter case the upperend of the arm or pendulum would be disposed at an angle to the lower portion thereof.

What is claimed is l. A bore sighting apparatus comprising an oscillatory sighting device, and means for supporting the device from a gun with its axis of oscillation coincident with and its line of sight bearing a predetermined relation to the critical axis of the gun bore.

2. A. bore sighting apparatus comprising an scillatory sighting device, and means for supporting the device from a gun with its axis of oscillation coincident with and its line of sight parallel to the critical axis of the gun bore.

3. A bore sighting apparatus comprising an oscillatory sighting device, and means for supporting the device from a gun with its axis of oscillation coincident with the critical axis of the gun bore'and itsline of sight.

parallel with and in the same vertical plane as the critical axis of the gun bore.

4. A boresighting apparatus comprising an oscillatory sighting device, means for supporting said device from a gun to be sighted, with its axis of oscillation coincident With the critical axis of the gun bore, and means for automatically positioning said device so that the line of sight determined by the device will bear a predetermined relation to the critical axis of the gun bore.

5. A bore sighting apparatus comprising an oscillatory sighting device, means for supporting said device from a gun t) be sighted, with its axis of oscillation coincident with the critical axis of the gun bore,

and gravity operated means for positioning said device so that the line of sight determined by the device will bear a predetermined relation to the critical axis of the gun bore.

(S. A bore sighting apparatus comprising an oscillatory sighting device, means for supporting said device from a gun to be sighted, with its axis of oscillation coincident with the critical axis of the gun bore, and means for automatically positioning said device so that its line of sight will be disposed parallel to and in the same vertical plane as the critical axis of the gun bore.

7. A bore sighting device comprising a member adapted to be supported from a gun with its longitudinal axis coincident with the critical axis of the gun bore, a pendulum mounted on the member With its axis of oscillation coincident with the longitudinal axis of the member, and a sighting device carried on one end of the pendulum.

8. A bore sighting device comprising a member adapted to be supported from a gun with its longitudinal axis coincident with the critical axis of the gun bore, a pendulum mounted on the member with its axis of oscillation coincident with the longitudinal axis of the member, and a sighting device carried'on the upper end of the pendulum determining a line of sight parallel to and in the same vertical plane as the longitudinal axis of the member.

9. The herein described method of sighting guns consisting in fixedly supporting the gun, positioning a sighting device with its line of sight parallel with the'critical axis of the gun bore, and then adjusting the gun sights into alinen'ient with said line of sight. 7

10. The herein described method of sighting guns consisting in fixedly supporting the gun, positioning a sighting device with its line of sight having a predetermined relation to the critical axis of the gun bore,

and then adjusting the gun sights into alinement with said line of sight.

11. The herein described method of sighting guns consisting in fixedly supporting the gun, positioning a sighting device with its line of sight parallel with and vertically above the critical axis of the gun bore, and then adjusting the gun sights into alinement with said line of sight.

In testimony whereof I hereunto affix .my signature 1n the presence of two witnesses.

CREEDY C. SHEPPARD.

Witnesses I CHAS. CHAl WBORN, EDITH STOWELL. 

